<template>
    <div class='sub-sort'>
      <div class="sort">
        <a :class="{active:sortParams.sortField===null}" @click="changeSort(null)" href="javascript:;">默认排序</a>
        <a :class="{active:sortParams.sortField==='publishTime'}" @click="changeSort('publishTime')" href="javascript:;">最新商品</a>
        <a :class="{active:sortParams.sortField==='orderNum'}" @click="changeSort('orderNum')" href="javascript:;">最高人气</a>
        <a :class="{active:sortParams.sortField==='evaluateNum'}" @click="changeSort('evaluateNum')" href="javascript:;">评论最多</a>
        <a @click="changeSort('price')" href="javascript:;">
          价格排序
          <i class="arrow up" :class="{active:sortParams.sortField==='price'&&sortParams.sortMethod==='asc'}" />
          <i class="arrow down" :class="{active:sortParams.sortField==='price'&&sortParams.sortMethod==='desc'}" />
        </a>
      </div>
      <div class="check">
        <XtxCheckbox @change="changeCheck" v-model="sortParams.inventory">仅显示有货商品</XtxCheckbox>
        <XtxCheckbox @change="changeCheck" v-model="sortParams.onlyDiscount">仅显示特惠商品</XtxCheckbox>
      </div>
    </div>
  </template>
  <script>
  import { reactive } from 'vue'
  export default {
    name: 'SubSort',
    setup (props, { emit }) {
      // 实现交互（实现交换的数据和后台保持一致）
      // 1. 明确交互数据
      const sortParams = reactive({
        inventory: false,
        onlyDiscount: false,
        sortField: null, // publishTime,orderNum,price,evaluateNum
        sortMethod: null // asc为正序，desc为倒序，默认为desc
      })
      // 2. 提供模板使用
      // 3. 需要绑定按钮的点击事件修改排序字段和排序方式
      const changeSort = (sortField) => {
        if (sortField === 'price') {
          sortParams.sortField = sortField
          // 处理排序
          if (sortParams.sortMethod === null) {
            sortParams.sortMethod = 'desc'
          } else {
            sortParams.sortMethod = sortParams.sortMethod === 'desc' ? 'asc' : 'desc'
          }
        } else {
          // 如果已经选项阻止运行
          if (sortParams.sortField === sortField) return
          sortParams.sortField = sortField
          sortParams.sortMethod = null
        }
        // 触发 sort-change 事件
        emit('sort-change', sortParams)
      }
      const changeCheck = () => {
        // 触发 sort-change 事件
        emit('sort-change', sortParams)
      }
      return { sortParams, changeSort, changeCheck }
    }
  }
  </script>
  <style scoped lang='less'>
  .sub-sort {
    height: 80px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    .sort {
      display: flex;
      a {
        height: 30px;
        line-height: 28px;
        border: 1px solid #e4e4e4;
        padding: 0 20px;
        margin-right: 20px;
        color: #999;
        border-radius: 2px;
        position: relative;
        transition: all .3s;
        &.active {
          background: @xtxColor;
          border-color: @xtxColor;
          color: #fff;
        }
        .arrow {
          position: absolute;
          border: 5px solid transparent;
          right: 8px;
          &.up {
            top: 3px;
            border-bottom-color: #bbb;
              &.active {
              border-bottom-color: @xtxColor;
            }
          }
          &.down {
            top: 15px;
            border-top-color: #bbb;
            &.active {
              border-top-color: @xtxColor;
            }
          }
        }
      }
    }
    .check {
      .xtx-checkbox {
        margin-left: 20px;
        color: #999;
      }
    }
  }
  </style>
  